Dra. Cléo Salustiano In this article
SummaryStep by stepWhy do time and storage matter so much?What happens at the dental office and afterwardsFAQRead nextTooth knocked out (avulsion): what to do in the first minutes
Quick summary of this article+
Permanent tooth knocked out: hold it by the crown, do not scrub the root, rinse briefly in milk or saline if dirty, put it back if you can or store it in milk, saline or saliva, and go to the dentist immediately — ideally within the first hour. Never keep the tooth dry. A baby tooth should not be put back. At the office, the tooth is repositioned and splinted to its neighbors, and a root canal is usually needed later. After a hard blow to the head, fainting or vomiting, go to the emergency room first.
A permanent tooth was knocked out? What to do now: hold the tooth by the crown (the white part), do not touch or scrub the root, put it in milk or saline — or, for a conscious adult, inside the mouth between the cheek and the teeth — and see a dentist immediately. Ideally, you should be seen within the first hour.
There is a reason for this care with time and with the root: the root is covered by cells that need to stay alive for the tooth to reattach to the bone. Out of the mouth and dry, they die within minutes. International dental trauma guidelines show that the outcome depends mainly on how long the tooth was out of the mouth and how it was stored.
If it is a baby tooth, the rule is different: a knocked-out baby tooth should not be put back, because this can damage the permanent tooth forming just above it. In this case, take the child to the dentist to check the mouth and the neighboring teeth.
This article comes from Dr. Cléo Salustiano's dental office in Mooca, São Paulo (care in English, Portuguese and Spanish). See the general dentistry page to learn how the treatment is done here and book your assessment.
Step by step
- Find the tooth and hold it by the crown. Always pick it up by the white part that shows in the mouth. Do not hold it by the root and do not scrape anything stuck to it.
- If it is dirty, rinse it briefly. Rinse it for a few seconds in milk or saline. Do not use soap, alcohol, hydrogen peroxide or a brush.
- Put it back in place, if you can and the person cooperates. Fit the tooth into position with gentle pressure and ask the person to bite on a clean cloth or gauze. If it does not go in, do not force it.
- If you did not put it back, store it properly. Milk or saline are the best emergency options. Saliva also works (inside an adult's mouth). Never keep the tooth dry in paper or a napkin.
- Go to the dentist immediately. Every minute counts. Send a message on the way so the team can get ready.
- Watch for signs of a more serious injury. After a hard blow to the head, fainting, vomiting, bleeding that will not stop or a deep cut on the face, go to a hospital emergency room first.
Why do time and storage matter so much?
The root of the tooth is wrapped in a thin layer of tissue, the periodontal ligament, which works like a "living glue" between the tooth and the bone. When the tooth comes out, these cells start to dry out. If they survive, the chance of the replanted tooth reattaching in a healthy way is higher.
That is why the tooth must never be left dry. Milk and saline keep the cells alive for longer because their composition is close to that of body fluids. Tap water is only an option if nothing else is available, and for as short a time as possible.
Scrubbing the root, washing it with soap or alcohol and holding the tooth by the root destroy exactly the cells you want to preserve. That is why the advice is to hold it by the crown and only rinse it briefly.
Even when everything is done right, the result is not guaranteed: it depends on the time out of the mouth, age, root development and injuries to the surrounding bone. Acting fast is what most improves the chances.
| Storage | Suitable? | Note |
|---|---|---|
| Milk | Yes | A good emergency option, easy to find |
| Saline solution | Yes | Keeps the root cells alive |
| Saliva (inside an adult's mouth) | Yes | Only if there is no risk of swallowing it |
| Tap water | Only if there is no other option | For as short a time as possible |
| Dry, in paper or a napkin | No | The worst scenario for the root |
What happens at the dental office and afterwards
At the appointment, the area is cleaned, the tooth is repositioned and attached to the neighboring teeth with a thin splint for a few weeks so it can stabilize. An X-ray helps check for fractures in the bone or other teeth.
In most permanent teeth with a fully formed root, root canal treatment is usually needed in the following weeks, because the nerve of the tooth generally does not survive the injury. Follow-up X-rays over the months show how the tooth is reattaching.
In the first days, the advice usually includes a softer diet, careful cleaning of the area and coming back on the agreed dates. No professional can guarantee that a replanted tooth will be kept, but fast care is the factor that helps the most.
If the tooth broke instead of coming out whole, see the guide broken tooth: what to do.
- Fouad AF, Abbott PV, Tsilingaridis G, et al. International Association of Dental Traumatology guidelines for the management of traumatic dental injuries: 2. Avulsion of permanent teeth. Dent Traumatol. 2020;36(4):331-342.
- Day PF, Flores MT, O'Connell AC, et al. International Association of Dental Traumatology guidelines for the management of traumatic dental injuries: 3. Injuries in the primary dentition. Dent Traumatol. 2020;36(4):343-359.
My tooth was knocked out. What do I do first?
+
Hold the tooth by the crown, do not scrub the root, put it in milk or saline (or in the mouth, between the cheek and the teeth, for an adult) and see a dentist immediately.
How long can a tooth survive out of the mouth?
+
The shorter the better. Ideally, you should be seen within the first hour. Dry, the root cells are lost within minutes; in milk or saline, they last longer.
Can I rinse the tooth under the tap?
+
Only if there is no milk or saline, and just for a few seconds. Never use soap, alcohol or a brush, and do not scrub the root.
Should I put the tooth back in?
+
If it is a permanent tooth, you know the position and the person cooperates, yes: fit it in with gentle pressure and have them bite on a clean cloth. If you cannot, store it in milk or saline and go to the dentist.
Can a knocked-out baby tooth be put back?
+
No. Putting a baby tooth back can damage the permanent tooth that is forming. Take the child to the dentist to check the mouth.
How can I tell if it is a baby tooth or a permanent one?
+
Age and size help, but it is not always easy. If in doubt, do not put it back, keep it in milk and see a dentist immediately.
Will I need a root canal?
+
In most replanted adult permanent teeth, yes, usually in the following weeks. The dentist decides the timing for each case.
Does a replanted tooth go back to normal?
+
Many stay firm for years, but the result depends on the time out of the mouth, how the tooth was stored and age. No professional can guarantee the outcome; follow-up shows how it evolves.
When should I go to the emergency room instead of the dentist?
+
After a hard blow to the head, fainting, vomiting, confusion, bleeding that will not stop or a deep cut on the face. In these cases, the hospital emergency room comes first.
The tooth came out and I could not find it. What now?
+
See a dentist anyway. It is important to check that the tooth was not pushed into the gum, swallowed or inhaled, and to look after the area.
The tooth did not fall out but became loose or crooked after the blow. Is it urgent?
+
Yes. A tooth that was displaced or loosened by an injury also needs a prompt assessment.
What can I eat after the tooth is replanted?
+
In the first days, soft, lukewarm food, avoiding biting with the front teeth. The dentist gives full instructions at the appointment.
Where can I get emergency care for a knocked-out tooth in São Paulo's East Zone?
+
At Dr. Cléo Salustiano's dental office (CRO-SP 170844), Rua Hipódromo, 1141 – Mooca, near Bresser-Mooca metro station, every day including Sundays and holidays, from 8 a.m. to 10 p.m. Message us on the way via WhatsApp +55 (11) 97409-7834. Care in English, Portuguese and Spanish.
